Western powers warn on violence in South Sudan
The three powers, the so-called troika that has led diplomacy and aid efforts aimed at stabilising the troubled young nation, urged all sides to ensure the safety of civilians in the southwestern area of Yei.
"This renewed violence risks undermining the peace agreement and lowers confidence of the troika and other international partners in the parties' seriousness and commitment to peace at a critical time," they said in a joint statement.
"We are concerned that if the situation escalates, the progress made in implementing the peace agreement will be irrevocably set back," they said.
South Sudan's government in September reached a peace deal with the main opposition unit of the Sudan People's Liberation Movement but a holdout rebel group, the National Salvation Front, rejected the deal.
Thousands of civilians in the Yei area have fled the renewed fighting and crossed the border to the Democratic Republic of Congo, according to the UN High Commissioner for Refugees.
South Sudan won independence from Khartoum in 2011 with fanfare from the West and billions of dollars in aid, but the country was immediately torn by internal conflict.
Nearly 400,000 people died and millions were displaced after President Salva Kiir accused his former deputy, Riek Machar, of plotting a coup.
The United States warned in December that it was finished with assisting South Sudan unless its leaders make peace.
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